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B234 woes, Any solid cam buckets/lifters in the US yet?

16V setting height

It is important to set the correct valve stem height for the 16V hydraulic lifters to work properly. The height is 49.4mm +/- 0.04 (=2 thou). This is measured from the top of a 30mm OD bar lying in the cam journals (which are 30mm ID) down to the top of the valve stem. I drilled 8mm dia holes in my bar so I could measure with the thin rod on a vernier micrometer from the top of the bar to the valve stem.
If you give this dimension to your cylinder head shop they can grind the valve stems to suit.
Dick Prince Ovlov.net
 
Well, bad news guys. I did a few more checks and the results don't seem good.

I tried a leakdown test with the cams removed, and I could only get 60-70% leakdown at best, depending on which cylinder. Just to be clear. I put in 100psi and could only hold 30-40 psi. Ive never seen such a leaky combustion chamber. I wanted to rule out any ring seal problems because the motor is 100% fresh and has never been fired, so I put a little oil into a couple of the cylinders to try and stop any ring gaps, and nothing seemed to improve. I guess the upshot, if there is any is that it looks like my leakage is isolated to the head and has nothing to do with the shortblock. Still quite annoying. I guess the head is coming off for sure. Bent valves? Bad valve job? What the hell went wrong?
 
More news. I pulled the head, and it looks perfect. I took it to my head shop (not the one with bongs) and he pulled a vaccuum on every port and the valves were sealing nicely. That was good news in a way. I still have no idea why I can't build compression, though I am ruling things out one at a time.

The only things left questionable are the rings. The motor has a fresh bore and hone. The rings came from the piston manufacturer and were filed to fit? Maybe, can't remember. I did measure the gaps at least and wrote down that the top and middle were both .018" gaps when installed. They might have been really close out of the box.

Could they be installed upside down? Wrong ring in the top groove? Would I get this problem by doing something silly like this? Or would it be somewhat normal for a motor that has never been fired leak this much? Doubtful.
 
I would not blame rings. Head bolts maybe too long? Guiderings too tall ? How did head gasket looked like when you lifted the head. Compressed or not?

Those are some good thoughts. It didn't leak water though. The gasket was imprinted nicely with all the water jacket marks and seemed to be compressed. Tonight I also bolted on an 8valve head from the garage and the leakdown was the same 60%, with no air coming out of the head ports at all.

can i ask a questions?

when they checked the vacum on the ports was the cam carrier installed with the cams in?

The cam carrier was installed, cams in, though not really bolted tightly together tightly. Just holding the parts together with finger tight nuts. And there were no lifters installed either. I wanted to see the results with the valves closed positively.

Wacky.
 
Yeah, I took measuerments on the stem length. And I think I am close. They are .010" too long, at the most,according the spec posted earlier, measuring from the cam journals.
That is still in the back of my mind too. But once I couldn't get compression with the cams removed, my theories were all de-bunked.

<sigh> still not sure where I'll find my lost compression. But I guess the bottom end is coming apart now too.
 
Yeah, I took measuerments on the stem length. And I think I am close. They are .010" too long, at the most,according the spec posted earlier, measuring from the cam journals.
That is still in the back of my mind too. But once I couldn't get compression with the cams removed, my theories were all de-bunked.

<sigh> still not sure where I'll find my lost compression. But I guess the bottom end is coming apart now too.


try to find some cylider block off plates that are used for leak down tests with the head off. Some shops have these ... might not be that easy to find, I dont know.
 
Not sure if you guys have ran into this in automotive, I work on small engines at work.

Hydraulic lifters can only be pumped up. If they are too large with the head assembled that the valves don't close, starting the engine up is not going to pump them down. They have a check valve as someone has already mentioned, and only pump up.

To bleed lifters down, rotate the camshafts so that the valves are all the way compressed. This puts a lot of pressure on the lifter and after some time the oil will bleed out of the lifter and it will compress, leaving some valve clearance. You will probably only be able to do 4 valves at a time, so keeping rotating the camshafts, do something else, rotate. 30 minutes should be more than enough time.

Upon start up, there is excessive valve clearance and the valves will tick. Oil pressure will fill the lifter until there is no valve clearance, like they are designed to do.

However, if the MS assembled the head to the cam carrier and installed the camshafts prior to doing the vacuum test, he should have run into this.
 
It Runs!

Well, I finally got the motor to start. Thanksso much to everyone here for all the suggestions. It really helped keep me going in the garage. I was really annoyed at first. I think I had a combination of problems that were adding up to my no-start condition before. I ended up removing the head, and double checking everything to find my problem. It was really confusing and I didn't really feel like I was finding the problem because everything seemed to check out. But here is what I finally did to fix the problems.

While the head was off, I put some STP engine oil treatment on the cylinder walls and turned the motor over to get the goop down in the rings. I suspected that my piston rings were quite dry. I can't even remember if I oiled them during assembly or not, but the motor sat for over a year, maybe 2 years since I assembled the shortblock. I wanted to lubricate the rings, and add something really goopy to seal up the rings enough to get the motor to build a "little" compression. I was hoping that if I could get the motor to start and run, that the dynamic compression would be sufficient to keep it running long enough to build some heat and seat the rings. STP is so old school, and I'm definitely not a snake oil user. But It was just the ticket for this application. My leakdown was 60-70% on every cylinder before. Though, I have doubts about my leakdown tester now. I didn't do a leakdown after lubing the rings, but I did a compression test once the head bolted on and my compression was back! I suspect lubricating the rings would have given me a decent leakdown test, but it was baffling how I could be losing that much pressure from just dry rings. Even my engine machinist was totally confused. He thought a motor with no rings in it would have at most 50% leakdown.

Second, and probably most important to good compression was a cam issue. :oops: I think I might have had the cams installed backwards before. Embarrassing. I wasn't sure, but I double checked the markings when re-assembling the motor to make sure the PZ1 was in the intake side and the PZA was in the exhaust side. After seeing the results I'm thinking I might have had this wrong before. You get no compression with the cams in the wrong sides. Though it didn't explain my poor leakdown, it did probably eliminate the compression.

I put it together and had 110psi on every cylinder. Not perfect, but it was a motor that was never run. Good enough to make it start I hoped. When I finally bolted it all together and set the timing close to where it needed to be, the motor fired on the 3rd try. The ignition timing was way off on the first 2 trys. The head mounted distributor has to be turned sideways with the wires pointing toward the passenger side to find the right timing on the 16v motor. This is still the 8v LH 2.2 distributor and it worked perfect turned sideways. There was even a bolt hole there to fix the timing.

It ran quite good, I let it run for 30 minutes at about 1500-2000 rpm. It went perfect, no leaks, no weird noises, just pure VOLVO music! I am going to change the oil this morning and try to find a muffler shop to re-connect my exhaust system so that I can really start the break-in.

I'm excited. Another T-bricks 16v turbo will be on the road soon. I'll try and get some pictures in a week or so after I move and get my camera out of storage.
 
Wow, good thinking. Smaller base circle cams. Hrrrmmmm.

Who should I contact about this sort of nonsense? It might be more economical than finding a set of solid lifters and a complete set of adjustment shims that I would need.

I have only had custom grinds from guys like Chet Herbert. I don't know if he could do a set of volvo cams. But probably. I have some connections. I might pursue this.

http://www.integralcams.com/custom_cams.htm

http://www.americancustomcam.com/custom_cam_grinding.php

I think comp cams may do it as well. You can also contact CHRFab and see if they'll give away the name of the place that does cams for them (or if they'll work with you anyway).
http://www.chrfab.com They have said before that they'll regrind cams on other motors besides what they specialize in (Northstars).
 
Well, since my motor is officially running now. I'm leaving things alone for a little while.

But since the cam topic came up again I wanted to add some comments. During all the scrambling in the last few weeks I did call American Custom Cams. And they could re-grind my cams if I sent them in for $75 each. Not bad for some extra performance, smaller base circle, whatever needed. They could even weld and grind any desired profile for slightly more money. I might consider this in the future. But for now I'm going to experiment with the PZ cams I have in the car now.

Did I mention I am stoked that the motor runs again?

It just came back from the muffler shop to get a mismatch in the downpipe to main exhaust fixed. Its all sealed up and "quiet" now. SCHWEET! The exhaust note is "interesting" Id say. I think the motor is louder out the exhaust now than it was with the 8v head. I know bigger cams sometimes have this effect on 8v cars. Just more noise out the exhaust valve when you hang them open longer. I think I might need a second muffler eventually. But for now, I'm enjoying the aggressive sound. It is loud enough that it might get annoying eventually. It definitely has the hippo fart sound. Not nearly as pleasing as a v8 rumble, but im sure I'll like it more once the boost goes up and the g's are pressing my ears backwards against the headrest.
 
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